Line-spacing mechanism



. Sept. 26, 1939.

LINE-SPACING MECHANISM Filed Oct. 20, 1934 2 Sheets-Sheet 1 Fly; 1

H, SCHULER Sept. 26; 1939. H, S HU ER 2,174,064

LINE-SPACING MECHANI SM Filed on. 20, 1934 2 Shets-Sheet' 2 Y ,ZW anim 4041 70 falazjef Patented Sept. 26, 1939 LINE- SPACING MECHANISM Hugo Schiiler, Chemnitz, Germany, assignor to Wanderer-Werke vorm. Winklhofer & J aenicke Akt.-Ges., Schonau-Chemnitz, Germany Application October 20, 1934, Serial No. 749,256

In Germany October 24, 1933 4 Claims.

This invention relates to line spacing mecha nism for typewriting machines having a spacing pawl carrier which is preferably capable of rocking, actuated by a spacing lever.

The objects of the invention are to simplify the adjustment for the different line spacings, to obtain an accurate and uniform spacing movement of the platen, and to make possible an approximately noiseless spacing. These objects are achieved by the present invention, namely, by the arrangement that the pawl carrier which makes contact preferably through spring action with the spacing lever carries a spacing pawl which is adjustable relatively to the line spacing wheel into different initial positions corresponding to dfferent line spacings.

In the drawings there is illustrated by way of example one form of construction of the mechanism according to the invention. In these drawings:

Figure 1 is an elevation,

Fig. 2 a corresponding plan view of the mechanism,

Fig. 3 is an elevation of a portion of the mechanism, on a larger scale, with the adjustment set for the smallest spacing,

Fig. 4 is a view corresponding to Fig. 3 but showing the adjustment set to the maximum 30 spacing,

Fig. 5 is a similar view showing the mechanism in its position at the end of the spacing movement, and

Fig. 6 is a section on the line 6-6 of Fig. 4.

n- The platen 3 is mounted in a portion 1 of the paper carriage with which portion is firmly connected a frame 2 supporting the line spacing mechanism. The frame 2 has a bore for the passage of the platen shaft 3a, on which is mounted the line spacing wheel or ratchet 4 d with teeth 5. At a short distance from the spacing wheel 4 a pin 6 is fixed in the frame 2 on which is pivoted the pawl carrier 8 which supports the spacing pawl I. The pawl carrier 8 is provided on the side facing the spacing wheel 4 with a recess H) which extends to the depth illustrated by the broken line 9 in Figs. 3, 4 and 5, which recess forms two webs II and I2. Between these webs II and [2 the spacing pawl l to can swing on its pivot pin ll.

The pawl carrier 8 is held at a definite distance from the frame 2 by means of a sleeve l3 surrounding the pin 6, and this carrier projects through an opening IS in the upper part of the 55 frame 2. On the pin 6 there is mounted a spring l4, one end of which projects into a hole l5 (Fig. 1) in the frame 2, while its other end projects into a hole IS in the web ll of the pawl carrier 8. This spring holds the pawl carrier 8 in contact with the line spacing lever 35 5 and it operates even when the spacing movement is finished, to restore the pawl carrier 8 and along with it the spacing lever 35, to the initial or normal position. To assist this action, there is provided a further spring 42 influencing 10 the spacing lever 35 in the same direction.

The pawl I mounted between the webs I l and i2 on a. pin I1 is under the action of a spring l8, which embraces the pin l1 and has one of its ends engaging a hole [6 in the pawl carrier 8 and the other end engaging a hole in the pawl l. The spring l8 urges the pawl I to turn always counter-clockwise and to hold a projection 22 of the pawl 1 in contact with a curved surface 23 on an adjusting member 24. 20

The pawl I has its operating tooth 2| located at a greater or lesser distance from the cooperating teeth 5 of the wheel 4, depending upon the setting of the pawl I, and during the spacing operation said operative tooth 2| will come sooner 25 or later into engagement with the teeth 5. Furthermore, a detent tooth 38 is provided on the pawl l, which, after the spacing wheel 4 has advanced a certain distance, will also come into engagement with the teeth 5 and prevent further movement of the wheel 4. By means of this engagement of the operative tooth 2| and the detent 38 of the pawl l, the beginning and the end of. the line spacing movement of the wheel 4 are exactly determined.

The adjustment member 24 consists of a knob provided with a gripping surface, which knob is rotatably attached to the carrier 8 by means of a screw bolt 25. The knob is provided on its upper surface with ascale division, as shown in Fig. 2, corresponding to the diiferent degrees of line spacing. For the exact determination of the various line spacings, a projection 21 on the knob is formed with flat faces 28 corresponding to the scale divisions, which faces form abutments for a leaf spring 29 bearing against them. The leaf spring 29 is fixed at 30 to the pawl carrier 8 and has a suitable hole whereby it is threaded on the pin 6. By means of a washed 3! and nut 32 the lower part of the leaf spring 29 is pressed against an extension of the pin 6 and thus forms a lateral stop for the pawl carrier 8 which rocks on the pin 6.

1 The cooperation of the leaf spring 29 with the struction would not result in any greater cost of the mechanism.

While the pawl carrier 8 rocks in a vertical plane in its operative movements in the frame 2, the line spacing lever 35 can swing in a horizontal plane about a pivot 4|! also mounted in the frame 2, said rocking being opposed by spring 42, so that its actuation during the return of the carriage can easily and simply take place by manual operation of the hand grip 35a. arm 39 of the spacing lever 35 carries a roll-or striking part 34 against which a yielding member 33 on the pawl carrier 8 makes loose contact under the action of the spring M. The yielding member 33 consists of a leaf spring which may be conveniently made integral with the leaf spring 29 of the adjusting knob 24. On rocking the spacing lever 35 and the pawl carrier 8, the roll 34 slidesagainst the yielding-member or spring 33. In this manner, without providing complicated connections, there is always a positive thrust between the spacing lever 35 and the pawl carrier 8. At the same time an entirely impactfree and noiseless transmission between the spacing lever and the spacing pawl is provided. A stop 31 is provided on the frame 2 which is adapted to cooperate with a projection 36 to act as a stop for thelever 35 in its inoperative pos tion, as shown in Fig. 2. The projection 36 is mounted on a short arm 4| of the spacing lever On the frame 2 there is also provided a check roll 43 pivoted about a pin 45 on a lever 44. A spring 41 urges the lever 44 always in the right hand direction, Fig. l, and holds the roll 43 in engagement with the teeth gaps of the spacing wheel 4 so that a movement of this wheel 4 will always take place tooth by tooth and the line spacings are maintained with accuracy. The pivot pin 45 is preferably adjustable by means of an eccentric device forming an exact and fine adjustment of the check roll 43. A hand lever 45 is provided for rocking the check roll 43 out of the operative position shown in Fig. 1 into an inoperative position, whereby the spacing wheel 4 and the platen 3 can be rotated as desired.

The operation of the mechanism is as follows:

By means of the adjusting knob 24 a determined separation of the operative tooth 2| of the pawl I from the spacing wheel 4 is set up. In Fig. 3, for example, the maximum separation of the tooth 2| from the spacing wheel 4 is illustrated, while Fig. 4 shows the shortest separation. In the first case, the pawl 'l' on rocking the pawl carrier 8 about the pivot pin 6 must first traverse a certain distance before its operative tooth 2| arrives in the position shown by broken lines and engages the teeth of the spacing wheel 4. In the second case, Fig. 4; the operative tooth 2| engages the teeth 5 soon after the commencement of the rocking movement of the pawl carrier 3. The beginning of the movement of the spacing wheel 4, and therefore the beginning of the rotation of the platen 3 is dependent upon the instant of engagement of the tooth 2| with the The wheel tooth 5. During the spacing movement of the spacing wheel 4 the pawl 1 will be rocked clockwise, Figs. 3 to 5, on its pivot pin against the action of its spring l8 until the detent 38 engages the teeth of the wheel 4, Fig. 5, and any further movement of the wheel 4, pawl 1, pawl carrier 8, and spacing lever 35 is then impossible and the spacing operation proper is finished.

On rocking the spacing lever 35 about its pivot pin 40, Fig. 2, the spring 33, which absorbs the first impact, is strained to a certain extent. The actuation of the line spacing mechanism thus begins very softly and without hard impact. During the further movement, particularly at the be- Finally, it abtent tooth 38 engages the teeth 5 of the wheel 4, said spring then being fully strained, Fig. 5. The whole line spacing operation thus proceeds very quietly and without disturbing noise. Both the setting of the different spacing adjustments and also the actual spacing operation can be performed very rapidly due to the simple mechanism and the reliable arrangement of the parts. The undesirable overrunning of the spacing wheel at the end of the spacing operation is reliably prevented. The'simplified assembly operates with a high degree of noiselessness and greater efliciency, while at the same time the cost of manufacture and assembly of the mechanism of the present invention is less than that of prior mechanisms for the same purpose.

I claim as my invention:

1. A line spacing mechanism for typewriters and the like, comprising in combination a paper carriage, aplaten mounted in a portion of the paper carriage, a ratchet fixed to the platen, a spacing pawl cooperating with the ratchet, a carrier in which the pawl is pivotally mounted, the carrier being mounted pivotally about an axis parallel to the platen, an adjusting member rotatably mounted about an approximately vertical axis on the carrier and having a curved surface in contact with the pawl for rocking the pawl about its pivot to adjust the initial position of the pawl on the carrier according to the spacing desired, a spacing lever pivoted about a vertical axis, a contacting member on the spacing lever coacting with the carrier, and a common frame for mounting said carrier and said spacing lever, said frame being mounted on said portion of said paper carriage.

2. A line spacing mechanism according to claim 1, in which the curved surface is on the underside of said adjusting member.

3. A line spacing mechanism for typewriters and the like, comprising in combination a paper carriage, a platen mounted in a portion of the paper carriage, a ratchet fixed to the platen, a spacing pawl cooperating with the ratchet, a carrier in which the pawl is pivotally mounted, the carrier being mounted pivotally about an axis parallel to the platen, an adjusting member rotatably mounted on the carrier and having a curved surface in contact with the pawl for rocking the pawl about its pivot to adjust the initial position of the pawl on the carrier according to the spacing desired, said adjusting member being provided with fiat faces corresponding to the desired positions of adjustment, yielding means provided for holding said member in the desired position, said yielding means being in the form of a flat spring secured to the carrier and cooperating With said flat faces, a spacing lever pivoted about a vertical axis, a contacting member on the spacing lever coacting with the carrier, and a common frame for mounting said carrier and said spacing lever, said frame being mounted on said portion of said paper carriage.

4. A line spacing mechanism for typewriters and the like, comprising in combination a paper carriage, a platen mounted in a portion of the paper carriage, a ratchet fixed to the platen, a spacing pawl cooperating with the ratchet, a carrier in which the pawl is pivotally mounted, the carrier being mounted pivotally about an axis parallel to the platen, an adjusting member rotatably mounted on the carrier and having a curved surface in contact with the pawl for rocking the pawl about its pivot to adjust the initial position of the pawl on the carrier according to the spacing desired, a spacing lever pivoted about a vertical axis,-a contacting member on the spacing lever coacting with the carrier, yielding means for holding said adjusting member in the adjusted position, the contacting member of the spacing lever including a rolling means adapted to roll on a flexible part of the pawl carrier and said yielding means and said flexible part consisting of integral flat springs, and a common frame for mounting said carrier and said spacing lever, said frame being mounted on said portion of said paper carriage.

HUGO SCHULER. 

